SAN FRANCISCO — Google’s wearable computer, the most anticipated piece of electronic wizardry since the iPad and iPhone, will not go on sale for many months.

But the resistance is already under way.

The glasseslike device, which allows users to access the Internet, take photos and film short snippets, has been pre-emptively banned by a Seattle bar. Large parts of Las Vegas will not welcome wearers. West Virginia legislators tried to make it illegal to use the gadget, known as Google Glass, while driving.

“This is just the beginning,” said Timothy Toohey, a Los Angeles lawyer specializing in privacy issues. “Google Glass is going to cause quite a brawl.”

As personal technology becomes increasingly nimble and invisible, Glass is prompting questions of whether it will distract drivers, upend relationships and strip people of what little privacy they still have in public.

A pair of lens-less frames with a tiny computer attached to the right earpiece, Glass is promoted by Google as “seamless and empowering.” It will have the ability to capture any chance encounter, from a celebrity sighting to a grumpy salesclerk, and broadcast it to millions in seconds.

“We are all now going to be both the paparazzi and the paparazzi’s target,” said Karen L. Stevenson, a lawyer with Buchalter Nemer in Los Angeles.

Google stresses that Glass is a work in progress, with test versions now being released to 2,000 developers. Another 8,000 “explorers,” people handpicked by Google, will soon get a pair.

Among the safeguards to make it less intrusive: you have to speak or touch it to activate it, and you have to look directly at someone to take a photograph or video of them.

“We are thinking very carefully about how we design Glass because new technology always raises new issues,” said Courtney Hohne, a Google spokeswoman.

Developers, however, are already cracking the limits of Glass. One created a small sensation in tech circles last week with a program that eliminated the need for gestures or voice commands. To snap a picture, all the user needs to do is wink.

The 5 Point Cafe, a Seattle dive bar, was apparently the first to explicitly ban Glass. In part it was a publicity stunt — extremely successful, too, as it garnered worldwide attention — but the bar’s owner, Dave Meinert, said there was a serious side. The bar, he said, was “kind of a private place.”

The legislators in West Virginia were not joking at all. The state banned texting while driving last year but hands-free devices are permitted. That left a loophole for Google Glass. The legislation was introduced too late to gain traction before the most recent session ended, but its sponsor says he is likely to try again.

In Las Vegas, a Caesars Entertainment spokesman noted that computers and recording devices were prohibited in casinos. “We will not allow people to wear Glass while gambling or attending our shows,” he said.

Louis Brandeis and Samuel Warren famously noted in 1890 that “numerous mechanical devices threaten to make good the prediction that ‘what is whispered in the closet shall be proclaimed from the house-tops.’ ”

Glass is arriving just as the courts, politicians, privacy advocates, regulators, law enforcement and tech companies are once again arguing over the boundaries of technology in every walk of life.

The Senate Judiciary Committee voted last month to require law enforcement to have a warrant to access e-mail, not just a subpoena. The Federal Bureau of Investigation’s use of devices that mimic cellphone towers to track down criminals is being challenged in an Arizona case. A California district court recently ruled that private messages on social media were protected without a warrant.

“Google Glass will test the right to privacy versus the First Amendment,” said Bradley Shear, a social media expert at George Washington University.

Google has often been at the forefront of privacy issues. In 2004, it began a free e-mail service, making money by generating ads against the content. Two dozen privacy groups protested. Regulators were urged to investigate whether eavesdropping laws were being violated.

For better or worse, people got used to the idea, and the protests quickly dissipated. Gmail now has over 425 million users. In a more recent episode, the company’s unauthorized data collection during its Street View mapping project prompted government investigations in a dozen countries.

Like many Silicon Valley companies, Google takes the attitude that people should have nothing to hide from intrusive technology.

“If you have something that you don’t want anyone to know, maybe you shouldn’t be doing it in the first place,” said Eric Schmidt, then Google’s chief executive, in 2009.

Glass is a major step in Google’s efforts to diversify beyond search, and potentially an extremely lucrative move. Piper Jaffray, an analyst firm, estimates that wearable technology and another major initiative, self-driving cars, could ultimately be a $500 billion opportunity for the company. In the shorter term, IHS, a forecasting firm, estimates that shipments of smart glasses, led by Google Glass, could be as high as 6.6 million in three years.

Thad Starner, a pioneer of wearable computing who is a technical adviser to the Glass team, says he thinks concerns about disruption are overblown.

“Asocial people will be able to find a way to do asocial things with this technology, but on average people like to maintain the social contract,” Mr. Starner said. He added that he and colleagues had experimented with Glass-type devices for years, “and I can’t think of a single instance where something bad has happened.”

An incident at a Silicon Valley event shows, however, the way the increasing ease in capturing a moment can lead to problems — even if unintentionally.

Adria Richards, who worked for the Colorado e-mail company SendGrid, was offended by the jokes two men were cracking behind her at the PyCon developers conference. She posted a picture of them on Twitter with the mildly reproving comment, “Not cool.”

One of the men, who has not been identified, was immediately fired by his employer, PlayHaven. “There is another side to this story,” he wrote on a hacking site, saying it was barely one lame sexual joke. “She gave me no warning, she smiled while she snapped the pic and sealed my fate,” he complained.

Critics lashed out at Ms. Richards, using language much more offensive than the two men used. SendGrid was hacked. The company dismissed Ms. Richards, saying there was such an uproar over her conduct, it “put our business in danger.”

“I don’t think anyone who was part of what happened at PyCon that day could possibly have imagined how this issue would have exploded into the public consciousness,” Ms. Richards reflected later. She has not posted on Twitter since.

A version of this article appears in print on , on Page A1 of the New York edition with the headline: Google Glass Picks Up Early Signal: Keep Out. Order Reprints | Today’s Paper | Subscribe